The chemistry core laboratory provides assays on a routine basis for individual projects within the program project. Established assays include measurements of renin activity, aldosterone, corticosterone, ANF, epinephrine, norepinephrine and ouabain. Projects which entail studies on potassium homeostasis in brain and fatty acid hypertension will use the chemistry core laboratory on a routine basis. The laboratory will assure quality control of the assays and provide consultation with individual investigators regarding appropriate use and interpretation of assays.